Carburetor



Aug. v19A 1924, 1,505,565

c. E. JOHNSON CARBURETR Filed Nov. 25 1915 ssheetsshegz 1 fumnnv @Xa/IWW l Aug. 194, 1924.

C. F. JOHNSON CARBURETOR F'led Nov. 26, 1915 3 Sheets-Sheet 2 Patented Aug. 1S, 19.24, i

l? NHTED STAT-ES "PATENT ortica.

CEESTER F. JOHNSON, OF DETROIT, HCHIGAN.

' CARBURETOR.

J Application led November 26, 1915. Serial No. 68,468.

To all whom z't concern.' Y

Be. it known that I, CHESTER F. JOHNSON, a citizen of the United States, and resident of Detroit, Wayne County, State of Michigan,

satisfactory mixture under various operating conditions. While maximum power may be produced in welldesigned motors equipped with prior carburetors when properly adjusted for certain climatic conditions and running with a wide open throttle; and while a motor, so equi ped, may easily have the proper mixture while running. under a so-called closed throttle condition, it has been found very diciilt to get the most satisfactory and elicient mixture atintermediate throttle positions and, therefore, most carburetors are4 adjusted to give the proper quality of mixture for maximum power when the throttle is wide open and they are also adjusted and designed, so that the proper quality of mixture 1s fed to 'the motor while running on the closed throttle position, which has been found tobe the most sensitive running position, regardless of intermediate throttle positions. In many cases, the mixture is far from ideal while the carburetor Ais' running `on intermediate position, or is operatin under different climatic conditions from t ose which it was adjusted for.V 0n the other hand, while maximum power can be obtained only with a 0115.03'.

nearly correct mixture, yet one ma excellent results with a mixture whic lis too thinlfor maximum power, and at the same time obtain greater fuel economy. Y

However, a carburetor, which will give'tlle proper'or desired mixture, at'any and all .p throttle positions, may be produced by providing means, as will be described; .such a carburetor may be provided with means 'for varying the quality of thek2 mixture, or for maintaining a mixture of the desired quality,

Aing the suction in the mixin ving t while the motor is'running i onpartially closed throttle ositions, without affecting the quality of t e mixture in the two more importantor extreme throttle positions; namely, closed and wide open.

To eliminate various difficulties heretofore encountered; to regulate 4and vary the quality of mixture for the most ideal motor running under diverse conditions, and to attain the desired results, I have provided means for varyin the. pressure on the fuel in the oat cham er, so that' the flow of fuel from the nozzle may be retarded or increased, with or without auxiliary air valves or supplementary' nozzles. This may be done by causact on the surface of the liquid in the fuel chamber, by means of a passa e connecting these-two chambers, and the egree of`suction throughthis passage may be controlled byl suitable valve means restricting the action of the vacuum therein, or by a'valve regulating the opening of a port connecting this passage with the pressure of the atmosphere, or by both.

- While the vacuum in the mixing chamber may be utilized for varying the pressure on the surface of the fuel in the float chamber, any other suitable means may be used and the valve mechanism for controllin the float chamber pressure may be operate by automatic vmeans responsive to temperature l i change, such as a thermally operated valve;v

it may also be manually controlled, orv one of the valves may vbe connected with the operating mechanism of the throttle lso that the opening and closing of the ports aiect-- e pressure on the liquid in-they oat chamber bears a definite. relation to thek throttle position. Thus, a carburetor may be produced whose eciency is not alteredl byvarying climatic or o erating conditions.

' A carburetor, provide with an auxiliary air valve of the vspring type, such as illustrated in the `accompanying drawings, may 'be so designed and the valve. closing spring maybe so adjusted to give the proper mixi .ture of gas at the slower'or throttled speeds Vof the motor, such as when idling, also when the throttle is wide'open. But with such an arrangement, the quality of the mixture may los not, as stated above, be properly maintained when thev throttle is only .partiall closed; therefore, the mixture becomes slig tly over rich in intermediate.positions.v On the otherchamber to vsigned and a and this qruality cannot be changed without cases, if the carburetor is dejusted to give the correct quality of mixture for maximum speed or power at' the o en throttle, or during very slow idling the rest of the'throttle movement some one (almost any one desired) quality of mixture,

hand, in man alteringeither the closed throttle or open throttle quality, or both.

To obviate this diiculty, the suction in the mixing chamber' may be brought into communication with the top of the float chamber when partially throttling the motor, thus decreasing the pressure therein, and retarding the iiow of fuel from the fuel nozzle, to produce a desiredmixture.

- It will be understood from what has beensaid that by proper designing of a carburetor comprising a single fuel nozzle and air intake passage, a carburetor may be designed, wherein the mixture may be maintained, by volitional or automatic control,

practically uniform, or varied at will, if desired, at all speeds of the motor and at all ranges of the throttle opening, if provided with my pressure regulator properly equipped with valve'means, the opening and closingvof which bears a proper relation to the positions ofthe throttle, or to the velocity of the gases owing through the carburetor, and, of course, the action of this valve means may be controlled or qualiiied by means sensitive to varying climatic conditions.

@ne of the objects of this invention, therefore, is to provide simple and efficient means for obtaining uniform or variable fuelv mixture, as desired, for'various speeds or throttle positions of `the motor.

Another oh]ect is to provide automatic means for maintaining the desired quality of mixture underdierent operating climatic conditions.

'-Other objects will appear from the following description, taken in connection with the accompanying drawings, which form a part of this specification, and in which:

, Figure l is a side elevation showing portions broken away, of a carburetor provided 'with an auxiliary air valve, and embodying a form of this invention;

Fi re 2 is a vertical sectional vieu7 substantially on the line 2-2 of Figure 1;

Figure 3 is a vertical sectional view of a so-called valveless carburetor embodying this invention; i

Figure 4 is a fragmentary vertical sectional view of a modified form of this invention Figures 5, 6 and 7 illustrate other modii',-f r

' f- It will be understood that the valve chamcations;

Figure 8' is a transverse sectional view of the modified form shown in Figure 7 substantially on the line 8 8 thereof; and

l #Figure 9 is a :fragmentary side elevation o the motor, it will give throughout in the center thereof.

of the regulating band and its securing means, as applied to the modification shownv in Figures and 8. v

`Referring to the drawings, particularly Figures 1 and 2, 10 indicates the main body, comprising an upwardly extending cylindrical portion 11, in which may be arranged a shaft 12, carrying a throttle 13. An operating arm 14 is suitably arranged on the shaft 1,2-, and has pivotally secured thereto an operating link 15 and a spring 16, which vmay be suitably secured at its oppositeend, as at 17, to the body '10. The lower portion/18 of the body forms a mixing chamberand is provided with an opening-19, across which is arranged a downwardly inclined diaphragm or partition 20, having a downwardly tapering mixing or carbureting tube 2l arranged It will be noted that the tube 2l is provided with p erforations 22 to permit drain-A ing od lof the fuel which may condense in the body and accumulate on the diaphragm.

A oat chamber is provided, which consists of a central member 23, comprising a head or' cover 24, and upwardly extending lugs or flanges 25, adapted to abut against .the diaphragm. The cover 24'is provided with a'port 26 and nipple 27, which is adapted to be connected with a source of fuel. rlhe cover is also provided with a downwardly extending channel 28, which also forms a seat 29 for a valve 30, which is adapted to be actuated by the usual float' 31,l

pivoted as at 32 to the'cover. ,A fuel nozzle of proper proportions, having a discharge port 33 and an intakeport 34, is illustrated as formed integral with the cover 24 and is formed with an internally threaded portion 35, in which may be arranged a plug 33, which also serves to hold a bowl or shell 3'? in position.

'lt will be noted that the cover 24 may be secured to the body 10, as by bolts 38 and is provided with a ylateral port 39, which is adapted to vhe protected b v the downwardly extending flanges 40 of the diaphragm 20.-

'lhis port, it will be understood, forms a primary intake for the air which is adapted to be directed downwardly by the diaphragm 20 and to be then drawn upwardly through the tube 21, after entering therein, as at 4l. Thenbody 10 has a portion formed integral therewith, extending llaterally from Ythe mixing chamber, forming a valve chamber 42, which has formed therein an auxiliarv air intake port 43, adapted to be closed by a valve member`44 and spring 45, which .is adapted to have a variable tension -ap- .plied thereto.

rber 42 is in constantcommunication with the mixing chamber 18.

' A mixture v regulator is provided, which will now be particularly described. Formed iso l l' provided with a port 43' at its inner end p nozzle and air passages are so proportioned communication with the mixing chamber and a port 44' is also provided at its outer end, in constant communication with an- .'other channel or groove 45', formed -in the body 10. Another channel or passage 46'is vprovided with a port 47 at its lower end,v communicating with the upper part of the oat chamber 48. It is also provided with a port 49 arranged at its opposite end in con-v lstant communication with the channels 45 and 42. .A valve member or shutter 50, which may be secured tothe throttle shaft 12, and operated thereby, is adapted to cause the ports 44 and 49 to communicate with the atmosphere, 0r to be cut off therefrom, so that they are left only in communication with each other. A valve 51 may be arranged in one of the channels, such as 43', and may be adapted to be operated through a suitable means, such as a bell crank 52 and the link 53, which may extend to a point adjacent the drivers seat, where it may be properly manipulated, or a threaded valve 51', such as shown in Figures 4, 5, 6 and '7, may be used. Another channel or vent 54, having a port 55 in thefloat chamber in constant communication with atmospheric y pressure, as atv56, is provided.

Having thus described the construction of the carburetor. shown particularly in Figures 1 and 2, the operation'will be under` .stood asfollows: It will be understood that when the throttle is almost closed and the motor is running idly, the primary air is drawn in the intake port 39, thence through the opening 41 and mixing with gasoline issuing from the fuel nozzle, as at 33, into4 the mixing chamber 18. Of course, as the suction of the motor increases, the auxiliary air valve 44 is opened and increases the supply of air to the carburetor.

With a carburetor of the general type, -illustrated in Figures 1 and 2, without a pressure regulator such as I have provided, the

and designedv that a proper mlxture is formed when the throttle is in the closed position and the motor is running slowly; and the tension on the spring 45 of the'auxiliary valve 44' is so adjusted that the carburetor will produce a satisfactory mixture for producing' maximum power of the motor while running on open throttle, but in many cases,

as indicated above, such a carburetor would not give a satisfactory or economlcal mixture while the motor 1s running on intermediate throttle positions. With, the adjustvments and` proportions of the various parts,

as described, the valve member or shutter 50 may be so arranged that just after the throttle is opened appreciably, the ports 44' and 49 have their communication with the atmosphere cut oil", so that the suction or vacuum inthe mixing chamber is caused to act through the channels 42', 45'-, andi46, directly on the surface of the fuel in the float chamber, thus ytending to decrease the pressure therein, and to retard the flow of fuel from the nozzle at 33. The valve 51 is f adapted to be adjusted to give the proper' vided for qualifyin or varying the mixture,-

as desired, for di erent throttle openings; this latter means being in the form of a valve 51,which may-be used to obtain the `most economical running mixture for the motor when maximum power is not desired.

It will be understood that the shutter 50 may be brought into action only while the motor is throttled, and in the form shown in the drawings the valve 50 is adapted to uncover the ports 44 and 49, bringing them into communication with the atmosphere when the throttle is wide open, so that in the open throttle position, the vacuum on the mixing chamber does not act directly on the surface of the fuel in the float chamber.

Referring particularly to Figure 3, it will be understood that this carburetor is not provided with an auxiliary air valve, the entire supplyof air entering the carburetor through the ports 39' and flowing downwardly therefrom to adjacent the lower end of the tube 21, thence it travels in the same direction, with the same function, and with the same resultas in the carburetor previously described. I am enabled to eliminate the auxiliary air valve, and obviate the necessity of supplementary fuel nozzles by propviding this carburetor with my float chamber pressure regulator, .which will now be particularly describe Sutably arranged in the upper part of the mixing chamber 18 is a transversely arranged tube 58, which may be revolubly mounted, and provided with a port 59 communicating with the mixing chamber. The tube is also provided with another port 60 in constant communication with a channel 61, provided with a port 62 in communication with .the upper part of the (float chamber 48. It will also be seen that operating means, in the form of a gear 63, is arranged on the tube 58 and secured thereto, inmesh and as the throttle is i throttle shaft 12, a's by they may `throttle 1s wide open, the

with a segmental gear 64 in 65. The ratio between these gears may e two to one, and be so connectedthat when the port 59 is in the position shown in the drawmgs, causing the full suction of the motor to be exerted on the surface of the fuel in the float chamber, gradually closed, the tube is revolved, so that when the throttle is iinally in closed position, the port 59 is turned downward, vso that the suction of the mixing chamber not only does not tend to decrease the pressureinl the ioat hamber, but, on the other hand, the incoming gas directed against the port 59 tends to increase the pressure in the ioat chamber. It is believed that the construction and operation of this so-called valveless carburetor, which is made posible by the use of my invention, will be clearly understood from the above description.

Referring particularly to Figure 4, it will be noted that in addition to the parts used in the carburetor, illustrated in. Figures 1 and 2, another channel 66, having a port 67 in constant communication with the mixing chamber, and a ort 68, adapted to be automatically broug t into communication with the iioat chamber, is provided, the latter port being adapted to be restricted by the tigr- 1s thermally operated valve member may be of any well known thermosensitive metal, and may be secured to the cover 24, as by the screw"70. This thermo res orsive def` Y vice is so constructed-that when t e temperature of the metal decreases, it contracts against the ort 68 closin the same, thus decreasing t e action on t e float chamber of the vacuum from the mixing chamber 18, andy vice versa. Y

`It will be clearly understood that this carburetor is provided with an automatic means sensitive l to temperature changes, whlch qualifies the fuel mixture accordingly.

- Figure 5 shows an application of athermally operated valve member 71, of circular `form, ,themixin' p 72, and aapted to-'close thev port 43', as the which may be secured inposition 1n chamber 18, as by pins or rivets temperaturecf the carburetor is decreased v the cover 24, as by screws 74, may be provlded, which is4 adapted to restrict the port c increases.

and to open the port.43- asl the temperature Another thermally operate valve member 7 3, which may be' secured to Y 47 when the temperature of the carburetor decreases; in other words, the action of a valve member 50, which is connected to the throttle shaft 12, may be qualified by either or both of these automatic valve members 71 and 73. i

. Figure 6 illustrates a carburetor which has a thermally 'operated-.valve member -76 secured to the cation of said ports with applied thereto, the valve member shown in Fi re 5. This carburetor is also provided with a circular thermally operated valve band 74, which is adapted to restrict the openingin .the port 56 in the vent or channel 54, thus decreasing the pressure in the float chamber as the temperature of the carburetor increases; thus the action of vthe valvel member or shutter 50 is qualified by an automatically .or thermally operated valve.

Figures 7,- 8

which has substituted in place of the shutter for the same purpose as.)

and 9 illustrate a carburetor 'l 'i is adapted to close o While I have illustrated and described lvarious modifications and applications of my invention, it will, of course, be' understood that they are merely illustrative, and various other modifications and changes ymay be made by one skilled in the art, wthoutdeparting'from the spirit and scope of the 1nvention intended to be covered thereby.

Having thus described my invention, what I claim and desire to ent is 1. In a carburetor, a fuelchamber -provided with a port adapted to communicate with the atmosphere, a mixing chamber pro- 'vided-with a port adapted to communicate.

a throttle valve, an-

with the. atmosphere, other valve adapted to controlthe communithe atmosphere, and interconnected means for operating said valves. v

2. In a carburetor, a throttle valve, a fuel chamber provided with an air passage, a mixingchamber providedwith an air passage, a valve for controlling the flow of air through one of -said passages, both of said passages being adapted to communicate with the atmosphere, and valve means operable d with said throttle valve for controlling the communication -of sald passages with the atmosphere. A i

3. In a carburetor, the combination with a throttle valve a fuel chamber provided With a port adapted Ato communicate with the atmosphere, and a mixing 'chamber provided with a port adapted to communicate with the atmosphere, of valve means operable with said throttle valve for closing oil the communication of saidv ports withthe atmosphere thereby causing the suction of the secure by Letters Patlll ' and adapted to cause the suction within the mixing chamber to vary the pressure on the fuel in the fuel chamber.

. 5. In a carburetor, the combination with a v`throttle valve a' fuel lioat chamber, provided with a passage adapted to connect a portion of the fuel .chamber above the'normal level-of the fuel with the atmosphere, and a mixin chamber provided with a passage adapte to communicate withthe atmosphere, of valve means operable with said throttle valvefor cuttin od the communicav nected therewith, and a spring closed valve v tion of said passages with the atmosphere,

'and a valve. adapted to restrict the opening ,A in one of sald passages.'

6. lln a carburetor, the combination with a lthrottle valve a fuel chamber, a mixing chamber, a fuel nozzlefeeding fuel thereto, a primary air intake and a'n auxiliary air intake also leading to said mixing chamber, said fuel chamber andsaid mixing chamber each being provided with an air passage adapted to communicate with .the atmosphere, and a valve operable with said throttle valve for connecting said passages together and'cutting 0E their communication with the atmosphere.

7. lin a carburetor, the combination with a oat chamber, of a mixin chamber, a fuel' nozzle and a plurality o air. intakes concontrolling the assage of air through one' ofsaid air inta es, said fuel chamber and said mixing chamber each being provided with an air passage adapted to communicate with the atmosphere or to communicate with 1 each other, a valve for connecting said pas-- v reservoir, a

sages' to ether, .,lafthrottle valve, and interconnecte means for operating both of said valves.l e

8. ln a carburetor, a carburetng chamber' having a throttle controlled mixture outlet Aand air and fuel-inlets, a constant level chamber suppl ing said fuel inlet with liquid fuel, and7 means operating with the throttle to-control the pressure in said constant level chamber for restricting the flow of fuel u on intermediate suctions and permitting ull How on high. suctions.

9. In acarburetor, a carbureting chamber I havin a throttle controlled mixture outlet and air and fuel inlets, a constant level chamber supplying said fuel inletwith liquid fuel, and means operating with the throttle to control the pressure in said constant level chamber for restricting the How of fuel u ort. v

intermediate suctions and permitting iow on high suctions'and low suctions.

1.0. In a carburetor, a carbureting chamber .having air and fuel inlets and a mixture outlet, a throttle in 'said mixtureI outlet, a reservoir for supplying said fuel inlet lwith liquid fuel, a restricted air .inlet for said assageway between sald chamber and sai reservoir over the 'fuel level therein, and means' operatingr with the said reservoir. V .11. In a carburetor, a carburetting chamber having a throttle controlled mixture outlet andfalr .and fuel inlets, n with which said fuel inlet isin communica-A" tion, a `oat therein and a va ve operated by said ioat to control the admissionof fuel to l throttle forcontrolling ya larger air inlet to said chamber, and means interconnected with vthe throttle to control the pressure m said float chamber-.for ,restricting the ow of fuel upon intermediate auctions and Permitting full How on high auctions.

Sinn n aomasoa In testimony whereof ax signature in the presence off'two vantnesses.l i 

